The invention relates to an elongate anti fret liner having a component for inhibiting movement of the liner in its direction of elongation. The liner finds particular application in a turbine engine.
Within a gas turbine engine some components, for example vanes, need to be restrained in a manner that resists the aerodynamic or other loads placed upon them during engine operation. The loads can be broken down into two primary components: the axial reaction load along the engine axis and the rotational reaction load about the axis. Both loads are typically transmitted from the gas washed components to a casing.
A gas turbine is an aggressive environment in which liquid lubricants cannot generally be used and materials with dissimilar material properties must make contact. Gas path static components tend to be constructed out of high strength alloys that make contact with casings that are generally constructed out of medium strength alloys. The different thermal coefficients of these materials and the large temperature range experienced by a turbine engine in operation means that it is not possible to rigidly join such components. Therefore the components can move relative to each other resulting in the possibility of wear, usually on the softer component.
To protect the two components an anti-fret liner that is made of material that is softer than either of the interfacing parts is positioned between the two components. Its purpose is to wear in preference to either of the interfacing parts and it may be considered to be a disposable part at engine overhaul. The anti-fret liner and any anti-translation features for the liner should accordingly be cheap to manufacture and easy to remove and replace during overhaul.
It is an object of the present invention to seek to provide an improved anti-fret assembly.